//
// Entity.h
//
// Library: XML
// Package: DOM
// Module:  DOM
//
// Definition of the DOM Entity class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef DOM_Entity_INCLUDED
#define DOM_Entity_INCLUDED


#include "Poco/DOM/AbstractContainerNode.h"
#include "Poco/XML/XML.h"
#include "Poco/XML/XMLString.h"


namespace Poco
{
namespace XML
{


    class XML_API Entity : public AbstractContainerNode
    /// This interface represents an entity, either parsed or unparsed, in an XML
    /// document. Note that this models the entity itself not the entity declaration.
    /// Entity declaration modeling has been left for a later Level of the DOM
    /// specification.
    ///
    /// The nodeName attribute that is inherited from Node contains the name of
    /// the entity.
    ///
    /// An XML processor may choose to completely expand entities before the structure
    /// model is passed to the DOM; in this case there will be no EntityReference
    /// nodes in the document tree.
    ///
    /// XML does not mandate that a non-validating XML processor read and process
    /// entity declarations made in the external subset or declared in external
    /// parameter entities. This means that parsed entities declared in the external
    /// subset need not be expanded by some classes of applications, and that the
    /// replacement value of the entity may not be available. When the replacement
    /// value is available, the corresponding Entity node's child list represents
    /// the structure of that replacement text. Otherwise, the child list is empty.
    ///
    /// The resolution of the children of the Entity (the replacement value) may
    /// be lazily evaluated; actions by the user (such as calling the childNodes
    /// method on the Entity Node) are assumed to trigger the evaluation.
    ///
    /// The DOM Level 1 does not support editing Entity nodes; if a user wants to
    /// make changes to the contents of an Entity, every related EntityReference
    /// node has to be replaced in the structure model by a clone of the Entity's
    /// contents, and then the desired changes must be made to each of those clones
    /// instead. Entity nodes and all their descendants are readonly.
    ///
    /// An Entity node does not have any parent.
    {
    public:
        const XMLString & publicId() const;
        /// Returns the public identifier associated with
        /// the entity, if specified. If the public identifier
        /// was not specified, this is the empty string.

        const XMLString & systemId() const;
        /// Returns the system identifier associated with
        /// the entity, if specified. If the system identifier
        /// was not specified, this is the empty string.

        const XMLString & notationName() const;
        /// Returns, for unparsed entities, the name of the
        /// notation for the entity. For parsed entities, this
        /// is the empty string.

        // Node
        const XMLString & nodeName() const;
        unsigned short nodeType() const;

    protected:
        Entity(
            Document * pOwnerDocument,
            const XMLString & name,
            const XMLString & publicId,
            const XMLString & systemId,
            const XMLString & notationName);
        Entity(Document * pOwnerDocument, const Entity & entity);
        ~Entity();

        Node * copyNode(bool deep, Document * pOwnerDocument) const;

    private:
        static const XMLString NODE_NAME;

        XMLString _name;
        XMLString _publicId;
        XMLString _systemId;
        XMLString _notationName;

        friend class Document;
    };


    //
    // inlines
    //
    inline const XMLString & Entity::publicId() const
    {
        return _publicId;
    }


    inline const XMLString & Entity::systemId() const
    {
        return _systemId;
    }


    inline const XMLString & Entity::notationName() const
    {
        return _notationName;
    }


}
} // namespace Poco::XML


#endif // DOM_Entity_INCLUDED
